Acriflavine is a topical antiseptic

Antiseptic

Antiseptics are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction...

. It has the form of an orange or brown powder. It may be harmful in the eyes or if inhaled. It is a dye and it stains the skin and may irritate. Commercial preparations are often mixtures with proflavine

Proflavine

Proflavine , also called proflavin and diaminoacridine, is an acriflavine derivative, a disinfectant bacteriostatic against many gram-positive bacteria...

. It is known by a variety of commercial names.

Acriflavine was developed in 1912 by Paul Ehrlich

Paul Ehrlich

Paul Ehrlich was a German scientist in the fields of hematology, immunology, and chemotherapy, and Nobel laureate. He is noted for curing syphilis and for his research in autoimmunity, calling it "horror autotoxicus"...

, a German medical researcher and was used during the First World War against sleeping sickness. It is derived from acridine

Acridine

Acridine, C13H9N, is an organic compound and a nitrogen heterocycle. Acridine is also used to describe compounds containing the C13N tricycle....

. The hydrochloride

Hydrochloride

In chemistry, hydrochlorides are salts resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base . This is also known as muriate, derived from hydrochloric acid's other name: muriatic acid....

 form is more irritating than the neutral form.

Acriflavine is also used as treatment for external fungal infections of aquarium fish.In recent years Acriflavine has been shown to have anti-cancer activity.